Roku tv to Pyle Amplifier

I have a ROKU TV (TCL55S425) with only HDMI outputs. (I am using the HDMI ARC PORT)

Through an HDMI to RCA composite video audio converter adapter

RCA connect to a Pyle Wireless Bluetooth Amplifier (P3301BAT)

I am not getting any sound. Help, please. So very frustrating.

FURTHER: how I might be able to have headphones (Bluetooth) and Pyle-connected speakers play at the same time? My husband works in a shop. Normally the speakers are fine unless he is going to use a loud saw. He would like to put on his headphone to listen without any steps. And then back again, as needed.

THANK YOU IN ADVANCE!